I'm sorry but what's a kokoronpa??!
Jokes aside, after completing the main story of v3, a few extra modes are available to play, Prison Mode is one of them. Instead of the students having to murder to get out, they must romance another character within 10 days to graduate. After you have completed the FTEs with a character, you can ask them out using “date tickets”. With a low chance, the date could become a “Kokoronpa” session. You, or Saihara, is able to hear the inner thoughts of the character, with their dialogue on the screen like it is in trials. You are given two word bullets, agree and disagree and the point of the Kokoronpa is to shoot the best bullet with the right phrase and get closer to the character. Yey~~
I hope this helped XXDD